


Natural Selection

by Saucery



Category: Teen Wolf (TV), The Avengers (2012)
Genre: Action/Adventure, Alternate Universe - Fusion, Alternate Universe - Movie Fusion, Alternate Universe - Superheroes/Superpowers, And Also Pantsless, Badass, Because Then You Know What You're Missing, Comedy, Crack, Crime Fighting, Crossover, Derek Hale Was Destined to Be Shirtless, Ensemble Cast, Frequent and Gratuitous Nudity, Geniuses, Humor, M/M, Mad Science, Multiple Orgasms, No Really It Is, None of This is Stiles's Fault, Pop Culture, Pseudoscience, Romance, Science Fiction, Sexual Content, Sexual Inexperience is Worse Than Virginity, Shower Sex, Stalking, Superheroes, Surprise!Sex, Technology, Werewolves, Women Being Awesome
Language: English
Status: Completed
Published: 2012-07-11
Updated: 2012-07-11
Packaged: 2017-11-09 15:26:56
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 5,965
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/457027
Author URL: https://archiveofourown.org/users/Saucery/pseuds/Saucery
Summary: <blockquote class="userstuff">
              <p>BEACON, also known as the Bureau of Enforcement, Armed Combat and Offensive Neutralization (it sure is <i>offensive</i>, Stiles thinks) has established the Avengers Initiative in order to, uh, fight crime. And rampaging alien hordes. And stuff.</p><p>Stiles is Iron Man. (Scott is Rhodey. Oh, Scott.)</p><p>Derek is the Hulk.</p><p>Lydia is Black Widow.</p><p>Allison is Hawkeye.</p><p>DANNY IS CAPTAIN AMERICA WHO EVERYONE LOVES.</p><p>Jaxon is a creepy alien dude with Daddy issues. And also Danny issues. Daddy Danny issues. Danny is justifiably alarmed.</p><p>Erica is Pepper Potts, except with more of an inclination toward bodily harm.</p><p>Chris Argent is the head of the Avengers Initiative. He is also fierce. He is also a silver fox. Hot damn.</p><p>And somehow, in the middle of all this chaos, the Hulk and Iron Man find love.</p>
            </blockquote>





	1. Chapter 1

**Author's Note:**

  * Translation into Русский available: [Естественный отбор](https://archiveofourown.org/works/1327618) by [CallMe](https://archiveofourown.org/users/CallMe/pseuds/CallMe)



* * *

 

He's down in the lab, tinkering with a new alloy that should, theoretically, withstand anything from nuclear missiles to alien projectile-claws with paralytic poison in them (thanks, Jaxon), when the Hulk crashes in the door.

And _prowls_.

Stiles stands there, surrounded by several billion dollars' worth of classified technology, while the Hulk… prowls. Back and forth. Back and forth. And growls, and paws at the floor.

"Um," says Stiles. "Should I get a tranquilizer dart? Or two? Or a million?"

The Hulk snarls. Muscles ripple beneath his fur; his eyes burn, red as the flames of hell.

Stiles gulps. "Oh-kay, then. If you want to kill me, do it later, all right? I've gotta finish this prototype, or BEACON will be up my ass. And not in the fun way, either."

The Hulk huffs. Paws the floor some more. And keeps pacing.

Fine. Dr. Deaton _had_ said that the best way to not get killed by a mutant werewolf was to _not run from it_ , and a wussy freakout would kind of put a serious dent in Stiles's street cred. The Hulk will leave soon, anyway. He doesn't have a reason to stay. That, and Stiles has a panic button embedded in his freaking spinal cord. He can take a bit of terror. Terror's good for concentration. It provides focus. Like a lens.

The Hulk's claws leave gouges on the concrete.

Stiles just… lowers his visor, grabs his laser-cutter, and gets back to work.

He gets lost in it, as he always does, the near-silent hum of the arc reactor a pleasant companion to the constant buzz of his mind, equations flitting in and out of it like bright, metallic birds. He pulls up a few holo-screens and sketches them, quick as he can, darting between application and theory, molecular models glittering in silver lines.

At some point, he starts whistling, juggling a pair of pliers back and forth. At some _other_ point, a cup of coffee materializes next to his elbow courtesy of a robot-hand - which he cheerfully shakes - and at some other-other-other point, the rumble of Stiles's stomach disrupts what he realizes is stream-of-consciousness dirty talk as he murmurs sweet nothings to his new alloy. Damn, she's pretty. And yes, she's a girl alloy. She's too pretty to be a boy alloy. Allison says gender stereotypes are stupid, which is a fair observation, since Danny's dimples are prettier than anything in the known universe, but still. This is one sexy alloy. It's the little black dress of metallurgy. The glorious lovechild of applied physics and chemistry. The -

"Sir," interrupts a botty voice. "You're hungry."

"Shove it," he says. "And I mean that literally."

Stiles opens his mouth, and freshly-replicated curly fries are summarily shoved into it.

He chews. Swallows. Spares a moment to close his eyes and make orgasm-noises, because the Cajun powder is to _die_ for.

Thankfully, the botty voice and its annoying interruptions (except for the fries, damn, those can _never_ be annoying) goes away.

He keeps working.

Danny is going to love this. It'll fortify his shield almost limitlessly, until no known threat can possibly put a crack in it, let alone destroy it. Modifying it to coat the fullerene nanogears in Stiles's own armor will be a slightly more complex task, but hey, complexity's his comfort zone. Complexity is to him what mojo is to Austin Powers. Yeah, baby, _yeah_.

Finally, at whatever o'clock, he's done.

Okay, he's never _done_ -done, but at least he's followed one of his gazillion trains of thought to its more-or-less logical conclusion and has produced something that'll give BEACON a collective boner the size of the Eiffel Tower, so. He's done. (For now.)

As if magically sensing his return to the human world, Erica strolls in with a file in one hand and a stylus poised like a weapon in another. What few people know is that it _is_ a weapon, and not just because Erica keeps stabbing him with it whenever he gets distracted during board meetings. It's also a mini-dart thrower and can release toxic gas into the face of whichever person offends Erica enough to deserve death. Which is practically everyone, eventually.

And now, it's Stiles. She's got that glower on her face.

God, she's going to insist he eats 'real food' again, isn't she? Curly fries are totally a valid food group; he's gotta change the FDA's stance on that. Maybe bribe a politician or two. Get a couple lobbyists in there. He can do that, can't he? It doesn't contradict the superhero moral code to manipulate national policies in one's favor, does it?

Damn it. It does. Stiles's inner Captain America (because Danny _is_ everyone's conscience) is so disappointed in him right now.

But, surprisingly, Erica doesn't say anything about Stiles's deplorable eating habits and how they're going to kill him slowly, so she might as well do him the mercy of killing him quickly. (She and Lydia must have slumber parties in which they bond over the myriad ways to intimidate, interrogate and assassinate people. Allison probably brings cookies to these cozy get-togethers, which - in Stiles's imagination, at least - always result in lesbian threesomes. Very giggly lesbian threesomes. In silk pajamas. And then _out_ of silk pajamas. Mm. And, yeah, maybe it'd all be more realistic with Allison and Lydia in matching black T-shirts with 'Budapest' printed on them in bloody scarlet, but Stiles prefers his fantasies.)

Instead, Erica points accusingly at a corner of the lab. The stylus glints. Like a knife. "What's that doing here?"

Stiles turns to look. "Huh?"

Oh. There's a -

There's a naked guy asleep in the corner of Stiles's lab.

A naked Derek.

A very naked Derek.

A very -

That's very -

Um.

"I can explain this," Stiles says, even though he can't, really. Had he seriously forgotten that there was a giant rage-monster in the _same room_ as him? Is he actually as suicidal as BEACON's asshat psychologists say he is? "He just, uh. Came in here. And by 'came,' I mean entered, not - not _jizzed_ , or anything. And by 'entered,' I mean - "

"Stiles. What is. He. Doing here."

"I don't know! How am I supposed to - "

Derek stirs. Groans. And settles, again.

Erica and Stiles glance at each other.

And back quietly out of the lab.

Very, very quietly.

Once they're out in the corridor, Erica grips his arm in a taloned hand (that isn't a manicure, it's a cat o' nine tails - well, five tails) and whispers: " _What is the Hulk doing in your lab?_ "

"Uh. He's not the Hulk?"

"Don't give me that bullshit. It wasn't Derek Hale that walked into your lab. It was - "

"Yeah, fine, it was the Hulk. Whaddaya want me to say?"

"Why didn't you _call_ someone?"

"What, his handlers? He's the Hulk. He doesn't _have_ handlers. Largely because, oh, _no one can handle him_."

"Officially, BEACON are his handlers."

"Officially, BEACON are jerkoffs."

Erica stares at him.

Stiles runs a hand over his hair. "Look, just - we trust him to fight with us, right? We're supposed to be a team. I don't - I don't want to call BEACON every time he acts up or fails to cool down after a mission or, or. Gets angry."

"He doesn't get angry; he _is_ anger. Pure, seething, frothing-at-the-mouth _wrath_."

"Yeah, but… his family was burned alive by his psycho ex-girlfriend and his uncle turned into a supervillain that genetically engineered himself _and_ Derek to be crazy vengeance-seeking monsters, and then Derek had to kill his uncle who was also his only remaining relative, and… that'd give any guy anger management issues, wouldn't it? I don't want BEACON coming in here and shooting him full of sedatives like he's some kind of goddamn - "

"Animal? Killer? Guess what, Stiles, he's both."

"He doesn't kill our own!"

"He tried to kill Lydia _last week_."

"That was because she was possessed by a supervillain's ghost! And you know which supervillain!"

"He. Almost. Killed her."

"But he didn't! …After BEACON shot him full of sedatives, sure, but - "

Erica crosses her arms. And raises her eyebrows. Her stylus taps her elbow like a fucking metronome.

"Fine, relax, I get it. I shoulda called BEACON. Big deal. All he's doing right this second is sleeping."

"How the hell could he fall asleep in there? With all the hammering and whirring and you talking like a lunatic?"

"Hey, I talk like a sane person!"

"You talk to your _self_."

"I talk to myself like a sane person!"

Erica snorts, and shoves the file into his arms. "Read that. And don't be late for the meeting."

"What meeting?"

"The one with Tarsus Pharmaceuticals, remember? The people working on healing serums? That _you commissioned_? By which I mean, I commissioned and you signed off on while nodding and pretending to pay attention?"

"Right. That. Good. Er." Stiles's throat clicks as he wonders how to put this. "Um…"

"I'll have some clothes sent up," Erica says, after watching Stiles stew in it for a couple minutes. Sadist. "He'll need to wear something, unless he enjoys nudity as much as a man as he does as a rabid wolf-creature. Not that his current body's half bad to look at…"

"Erica!" Stiles doesn't mean to sound like a scandalized grandma - or a scandalized chipmunk - but the indignant squeak escapes him, anyway.

"What? Not like _you_ weren't checking that out."

"Nonsense. Sacrilege. Danny and Lydia are the only superheroes in my heart!"

"But not in your pants. Clearly."

"Stop mocking my lifestyle of absolutely voluntary chastity. That has nothing to do with my being unable to hook up with my godlike teammates or with human beings in general."

"Or aliens."

"Or aliens, yes, thanks for the Jaxon reminder. Like the venom still working its way out of my system isn't enough of a reminder to never flirt with Danny when Jaxon's within hearing distance or, uh, _hissing_ distance - "

"Stilinski," says a gruff voice, behind them, and Stiles whips around, instinctively putting Erica behind him.

Erica pokes him in the back with her fingernails. She doesn't like being patronized. Well, tough fucking luck.

Derek's standing in the doorway, leaning against the jamb, completely nude. And completely unselfconscious, or at least, that's what it _looks_ like, until he says: "Get me some clothes."

"Sure," says Stiles, and surreptitiously pushes Erica in the direction of anywhere-but-here. "I'll do that. Why don't you - would you like - coffee? Maybe?"

"Won't work on me. Metabolizes too fast."

"Of course. I - sorry, I. Maybe you'd like to… go back inside? For the time being? To prevent random passersby from pissing themselves in fear and/or creaming their pants in lust, because yes, those are generally the effects you have on people?"

Derek glares at him, dully, like he still isn't quite awake. And goes back inside.

"Wow." Stiles goggles. "It's been ages since I've even seen the Hulk's human side. Let alone talked to it. Him. I mean him."

"And yet you go out of your way to defend his honor and give him shelter," Erica drawls.

"I don't - "

"I'll send the clothes up. Oh, and remember to have food for dinner. Actual food. With actual nutrients. Which, for the record, do not include coolants or curly fries."

"Ha bloody ha," Stiles calls after her, as she turns and sashays away. Her hips are perfect sine curves. "The coolant thing was an accident! There was a bottle! It had a straw in it! I just -"

But Erica's just shaking her head as she leaves.

So. Back to his lab. Where a naked sometimes-monster is inexplicably waiting for him.

No. For _clothes_. For - for clothes. Yep. Not Stiles. Why would a naked sometimes-monster be waiting for Stiles?

 

* * *

 

Turns out, he _is_ waiting for Stiles. If by 'waiting' one means 'stalking one back to one's lab and proceeding to terrify one out of one's wits.'

Much to Stiles's consternation, it's sort of become a thing. That Derek does. That the _Hulk_ does.

This is how it pans out:

The Avengers go out for a mission; the Avengers come back to the mansion.

Black Widow typically heads up to her room to clean all the blood off her form-fitting latex outfit. Which is a process Stiles spends entirely too much time thinking about. Lydia is _hot_ , okay? Especially when she's got that fresh-kill afterglow.

Captain America typically gets mobbed just outside the mansion, and fends off - or _fails_ to fend off - overeager journalists with flashing cameras. Danny's way too chivalrous to turn down kiddy reporters from school newspapers, and ever since the media conglomerates realized this, the ages of the journalists approaching Captain America have been dropping steadily. Stiles fully expects to see a toddler waving a microphone, one of these days.

Hawkeye typically cleans her arrows with the sort of tender, pornographic attention that would give Scott a boner if he was ever around to witness it, which he's not, which is why she calls him up and they have phone sex, instead. Stiles only knows this because of that one time he is definitely not thinking about. Also, he does _not_ want to know why Allison was giggling about bestiality. Just. No.

The Hulk… typically disappears to brood and claw pensively at wallhangings or whatever he does when he's in the middle of his angsty disappearing act, except that these days, his disappearing act is far less effective because it takes place in _Stiles's lab_. Where Stiles can see him. Not very effective, insofar as disappearances go. Stiles even considers finessing that nanobot invisibility cloak so that it'll hide the guy until Stiles is done with his work. Keep him out of sight, out of mind.

It's not even -

It doesn't make any _sense_.

Especially given the fact that when Derek is in Hulk mode, he's pretty much preverbal, so it's not like Stiles can _talk_ to him. At him, sure. (Stiles does that a lot.) But not to him. Or _with_ him.

And yet, somehow, in-between all the prowling and huffing and puffing, Derek… stays. As Stiles works. And falls asleep, right there, in a corner of Stiles's lab. Curled up like a - like a -

Like a very large, very muscular, very naked man-puppy.

Stiles is considering the pros and cons of a doggy basket. Pros: Doggy basket. For the Hulk. Heh. Cons: Getting killed _by_ the Hulk. Possibly eviscerated. Hm.

It's a tough choice. In the end, though, Stiles opts for saving his neck, and doesn't get anything for Derek other than a collection of spare clothes, tailored specifically to fit his gargantuan shoulders. Those shoulders are like Mount Rushmore. Each one of Derek's shoulder-muscles is the president of its own small country with an obscenely high GDP. Jesus _Christ_.

Erica theorizes that, due to Derek's mental instability, he finds Stiles's babble soothing.

Stiles just thinks it's the lab fumes. The Hulk must get high on lab fumes. Never mind that there _are_ no fumes, because Stiles has sentient air purifiers that don't just purify the air, they analyze every kind of atmospheric emission from the radioactive to the yes-okay-boring. (Anything that isn't radioactive is boring, as far as emissions are concerned. Or as far as anything else is concerned. Let's face it; stable isotopes just aren't interesting.)

He - he gets used to it. Somehow. Beautiful machinery in his hands, beautiful not-always-rage-monster at his back. Maybe it's Stockholm Syndrome. Maybe it's a hostage situation gone… right. Wrong. So wrong that it's right.

Whatever the case, he and Derek seem to have an unwritten 'Don't Ask, Don't Tell' rule about it. Stiles very carefully doesn't ask what the hell Derek is doing here, and Derek shows no inclination of explaining his attachment to all things - lab. Lab, obviously. Not Stiles.

The rest of the team thinks it's hilarious, but they're too scared of the Hulk to bring it up in front of Derek, in case it makes him lose his temper. (Hah! That's an understatement; Derek doesn't lose his temper, he goes _berserk_.) So, naturally, the butt of all their puppy jokes and mating jokes (and, on one tasteless occasion, _knotting_ jokes) is Stiles. Lydia takes a particularly malicious joy in pointing out that Iron Man can't pick up any girls, but has no trouble picking up stray mutant wolves. Haha. Very funny.

Danny is weirdly relieved, which is horrible, because a) it's not like Stiles was hitting on him _that_ much, and b) it's not like Stiles and the Hulk are having some sort of exclusive relationship that precludes Stiles flirting with other people.

But no matter how much Stiles tries to _explain_ that to other people, they still seem to worry about getting their heads ripped off, because they sort of go all… pale-faced when Stiles smiles at them or gives them casual compliments about their hair or their firearms. Even the one sweet-faced BEACON agent who'd tolerated him has started avoiding him, now, because she melts away like the world's prettiest ice cube when he's around. It's tragic.

He tries to whine to Scott about it, but Scott only snickers over the phone and repeatedly says the word 'bestiality'. In exactly the same tone Allison had said it.

Seriously. Those two. Stiles doesn't want to know what's going on in their heads.

 


	2. Chapter 2

* * *

  


It's another Tuesday on the East Coast, which means it's Villain of the Week time. _This_ time, it's your run-of-the-mill mad scientist with a slightly less run-of-the-mill attack plan. An attack plan involving giant bees with a hive mind. Evil, poisonous bees that are almost impossible to destroy, because each individual bee knows and sees what all the other bees are knowing and seeing, so the Avengers can't ambush them or attack one of them without all of them clueing in.

"You're a scientist!" Stiles yells through his helmet, zooming between skyscrapers and dodging bee-stingers the size of his _legs_. He sweeps two innocent bystanders off a nearby balcony and deposits them on the ground, before revving up and returning to the fray. "You should really look into this global swarming problem! Ice-caps! Will no one think of the ice-caps?"

"That has nothing to do with bees," Danny deadpans, in Stiles's ear-piece, and Stiles rolls his eyes.

"It so does! It's like the butterfly effect. The beat of a single pair of wings can - "

"Bees aren't butterflies."

"They're anthophiles! Same difference!"

"If you two could stop geeking out," Allison's voice crackles over the comm, "then maybe someone could cover me while I go over Wyndham Tower?"

"Oh, hell to the no," says Stiles, narrowly avoiding another stinger. "Scott'll kill me if I let you - "

"Do it."

And that's a command. A stone-cold command. Of stoniness.

Stiles sighs, drops in to grab Allison and carries her up to the top of Wyndham Tower, where she proceeds to shoot down more bees than Stiles can _count_ in, like, fourteen seconds.

Maybe Scott _is_ a moron to tell Stiles to watch out for her.

"Hawkeye, has anyone ever told you that you remind them of a William Blake poem? That you have a fearful symmetry? No?"

"That's very flattering, Iron Man, but your boyfriend's wrecking public property."

"He's not my - "

"I didn't even have to mention who it was, did I?"

Well, fuck.

Stiles gets Danny to cover her, instead, and rockets back down to lift the Hulk out of the nest of smashed concrete and bee-parts that he's built for himself. Unfortunately, most of the concrete seems to belong to public works, such as the mayor's self-aggrandizing statue and the ugly-ass fountain it was stationed in the center of.

Hell, maybe the Hulk has a hidden talent for interior decoration. Or exterior decoration. Since this is, uh, outdoors.

But for now, Stiles has to get him away from said public works and put him in a place where his destructive power is more strategically deployed. (Colonel Argent's words, at the last briefing. Not his.)

Stiles hooks his arms under the Hulk's armpits, and lifts.

The Hulk _roars_.

"Ow! Stop clawing at me!" Not that Stiles can actually feel the Hulk clawing at him, but his armor sparks spectacularly under those savage paws, like Stiles is a firework and this is the fourth of July. Or a Katy Perry music video.

Good thing he coated his armor with the new alloy. Otherwise, subjecting it to the Hulk's claws would be like putting it through a shredder. A very angry shredder. Weighing several kilotons.

Stiles has to boost his suit up to 238% percent of its capacity just to be able to pick the Hulk up and move him. Which is icky enough considering all the gooey bee-corpses stuck to the Hulk's dark fur, but finally, Stiles gets to the middle of the swarm of bees and sets the Hulk down.

Or tries to. Because the Hulk has Stiles's _head_ in his _jaws_.

"Iron Man," shouts Lydia, from the other side of a field of yet more squashed insects, "are you aware that the Hulk is biting your head off?"

"Sure am," Stiles says. "Not like I could've missed the pointy fangs making scratches on my helmet, _ow_ \- "

"Can't say I blame him."

"Gee, thanks, Black Widow. I appreciate your vote of confidence. How about getting him off me?"

"Ain't _my_ job to get him off."

"What…!"

"Oh, don't pretend to be shocked. By the way, I've figured out how to stop the bees. I need you to cover me."

"Why do all the beautiful girls want me to cover them, but not sexually?"

"Maybe because nothing about you is remotely sexual?"

"Ouch. That hurts _way_ worse than what the Hulk's doing to me right now."

"You're welcome. Anything to take your mind off the pain."

"You're so giving."

"I know. Now, ditch the fur-ball and cover me."

Stiles ditches the fur-ball. With some difficulty. Which is to say, he almost doesn't manage it, at all. It's only the advent of a fresh spate of serial killer bees that distracts the Hulk enough to start leaping at them instead of leaping all over _Stiles_.

Thank god.

He flies across to Lydia and holds his hands out. "Iron Man escort service! At your, um, service."

"I do not ever want to hear the words 'escort' or 'service' from your mouth again, are we clear?"

"Yes, ma'am."

" _Or_ ma'am. Call me that again, and you'll be dead before you finish talking."

"Yes, m… mistress of the universe."

"Good." She steps into his embrace. "Target's at two o'clock. The one with the bluish stripe. It's the queen."

And up they go. Lydia's a lot tinier in his arms, curvy and fragile, but, arguably, more deadly than the Hulk could ever be.

She leaps from his hold onto the back of this blue-striped bee, and then pulls some sort of crazy karate chop that _beheads the bee with one strike_ , holy shit, and makes all the _other_ bees fall, too.

It's only in the sudden, all-encompassing silence that Stiles realizes just how loud all that buzzing had been. In fact, the new silence is so deafening that Stiles's ears almost pop.

Lydia just lands daintily on her feet, delicate as a snowflake, and flicks the bee-blood off her fingers.

Yeah. _Definitely_ more deadly than the Hulk.

"How'd you know it was the queen?" Danny pants, later, after making sure that all the civilians are safe and that there's no one buried under the rubble, or something.

"Takes one to know one," says Lydia, sweetly.

Stiles couldn't agree more. Even though he knows that Lydia probably worked it out by calculating complex trajectories and flight paths and combat patterns in her head. Badass mathematician superheroine that she is.

The mad scientist had apparently synced his consciousness with the queen bee's, which means that when Lydia killed it, the scientist fell over, twitching. He's been apprehended by army personnel, now that he isn't keeping them at bay with ginormous flying insects, and now that Scott, as the Avengers' military liaison, can take his troops in without getting them pincushioned by stingers.

Awesome. Mission accomplished. Day saved. Et cetera.

As always, Danny fails to keep the now-omnipresent reporters at bay, until Lydia comes forward and _smiles_.

The reporters… shrink back.

Allison doles out sympathetic-but-steely smiles of her own, and the Hulk inadvertently scares the bravest paparazzi out of their minds, so at long last, the Avengers get to go home.

They head back to the mansion, leaving the city's clean-up to BEACON, which is about the only thing they're worth working for. Party's over. Nobody likes doing the dishes. Or the, uh. The sidewalks.

The Hulk, of course, follows Stiles to his lab - not an unusual occurrence - but what's unusual is that he _also_ follows Stiles to his apartment, after Stiles's robots have taken his armor off him, and Stiles, for reasons beyond his own understanding, lets him in.

And immediately starts babbling, because what else can one do in such a situation?

"I know you tried to _eat_ me, earlier today, but I'm tired, and also my neck hurts where you unknowingly wrenched it, not that I hold you in any way responsible for your actions while under the influence of an uncontrollable rage-fit, but it's been a sucky day and I could really use a hot shower. So, help yourself to my couch and try not to tear it to bits, okay? Okay. I'll be back."

Stiles goes in for a shower, closing the door behind himself and stripping before standing under the heavenly, _heavenly_ spray, and he's so transported by delight and so boneless with exhaustion that he almost doesn't notice the door opening behind him.

Almost.

"Er." Stiles blinks away a few drops of water. And turns to see Derek standing there, naked as he always is after turning back into a human, and damn, is it just Stiles, or has this been the quickest transformation _ever_? Also, how wrong is it that even covered with bee-guts, Derek's body glistens like a gift from the gods?

"I'm sorry," Derek says, and Stiles is so startled that he almost slips and concusses himself against the shower-head.

"Wh-what?"

"I injured you." Derek gestures at Stiles's neck. Which still aches, and which must have a big, bad bruise all along it and down his right shoulder, too, because Stiles can feel the twinge when he moves.

But still. "You're the Hulk," Stiles says, dumbly, eyes widening as Derek steps toward him. "The Hulk never apologizes."

And Derek climbs right _into_ the shower. "I'm not the Hulk," he says, dangerously, calmly, like it's the most obvious thing in the world. "I'm Derek Hale."

"Right. That's - that's a nice Dissociative Identity Disorder you've got going, there, real Jekyll and Hyde stuff, ever thought of getting a therapist? Possibly a therapist that can help you come to terms with the concept of _personal space_? Oh, god, you're in a shower with me, you're _naked_ in a shower with me, you're - "

"I'm dirty."

"You're filthy. And I'm gorgeous. No, wait, stop incepting me with Scissor Sisters lyrics - "

"Shut up."

Stiles… shuts up. And _breathes_. And presses himself back against the tiles, as far away from Derek as he can, because sharing nudie shower-time with the Hulk's human counterpart wasn't exactly what he'd penciled into his schedule for today. Handing the Hulk's human counterpart the soap so that he can wash insect juice off of himself? Not part of his plans, either.

Derek is - Derek is kind of unbelievably pornographic, all flexing pectorals and flawless deltoids and miles and miles of wet, gleaming skin, and also Derek has a boner, and also the water's too warm now that Stiles is heating up from _within_ , flushing with inevitable, utterly disastrous lust.

Derek narrows his eyes. "I can smell you."

"And I can _see_ you, all right, it doesn't take super-senses to make out the massive hard-on that you for some reason have. Uh. _Why_ do you have…?"

"You have one, too."

"I do? I do. Crap. Um, can we just ignore - "

"No." Derek crowds him against the wall and buries his face in Stiles's throat, no hesitation, no sense of, oh, _propriety_ or asking for permission or taking Stiles out to dinner, first. Unless…

"Have we been dating? Have you been stealth-dating me? Is that what all the stalking was about?"

Derek grunts. And mouths at Stiles's neck, making Stiles shiver despite the heat that seems to be reducing him to ash from the inside out.

"Have we been - oh, _fuck_ , don't - "

"I put that on you," Derek rumbles, running a callused palm over the bruise on Stiles's neck, and then down his back, cupping his ass.

"Y-yeah. You did. Look, we should talk - "

"I put that on you," Derek repeats, like a broken record, and his eyes are glowing red.

Shit. Panic button, panic button -

"Focus, Derek. _Focus_. On talking? That thing we need to do? Before ruining our healthy working relationship that only occasionally involves murder attempts but is otherwise a perfectly peaceful balance of involuntary cohabitation and non-consensual stalking? Hello? Let's _talk_ \- "

"You talk too much," Derek growls, and then his lips are on Stiles's mouth and his fingers are wrapped around Stiles's dick, and Stiles is gasping and scrabbling against the shower tiles and coming his brains out, and Derek's purring, or maybe snarling, Stiles can't tell the difference, and prickles of unbearable brightness sizzle through Stiles like an electrical storm, and it's -

It's too huge, too blinding and jagged and sharp and complete, and for one terrifying, dizzying instant, Stiles isn't sure he'll remember who he _is_ when it finishes, if he'll ever feel whole again -

Derek's hand won't stop _moving_ -

And Stiles keeps coming, over and over, jaw dropping open and body shaking like a goddamn leaf, like it's trying to get away from itself or trying to find itself, and he still can't look away from Derek's eyes, his mad, burning eyes, because even if Stiles does get away, those eyes will always find him -

Fuck -

Damn. That's all he has to give. That's all he _can_ give, and as if Derek can see that, or - or smell that, that's when Derek stops. He's still hard, and still breathing heavily, but mercifully, he _stops_ , and swipes a come-slick palm up Stiles's thigh, under the running water, before reaching to turn the shower off.

Stiles is literally seeing stars.

...wow. _Wow_. So this is what sex feels like. Stiles had almost forgotten.

It feels _great_. Even if it leaves Stiles wooly-headed and pasta-limbed and weirdly trembly, quivering with aftershocks, like his entire nervous system was the ground zero of a ten-point earthquake. His knees refuse to lock. His joints refuse to work. It's bad enough that Derek has to carry him out of the shower and into the bedroom, which is embarrassing, he isn't a damsel, he's supposed to be the one _rescuing_ damsels -

"Are you hurt," Derek says, and it isn't even a question. Certainly, Derek isn't waiting long enough for an answer, his hands running over Stiles like Stiles is their property, like they ought to know everything about him, because he's _theirs_.

"No," Stiles chokes. "No, but maybe - you could wait, I'm a little - " _sensitive_ , he doesn't get to say, because Derek's biting his mouth again, gently, and then his Adam's apple, and then his nipples, and Stiles is starting to wonder if that bee-juice had hallucinatory properties, because there's no way any of this can be happening, and if Stiles is forced to come again, so soon, he's going to pass out. He's absolutely going to -

"S-stop. If you - I haven't even gotten to touch you, yet - "

But Derek just pins his wrists to the bed and swallows his dick.

Stiles thrashes and _screams_ , and experiences the distinct sensation of his eyes rolling back in his head.

It's the last sensation he remembers.

Because he passes out.

Of course he does.  


  


* * *

  
When Stiles wakes up, sandy-eyed and more relaxed than he can recall being in, like, _ever_ , he's still vaguely resentful about being made to come all over himself like a freaking virgin (which he's not) and not being allowed to touch Derek _back_.

There's a fundamental injustice in that, not just because Stiles didn't return the favor, but because he didn't get to see Derek _come_. Then again, if Derek's orgasms trigger an episode of Hulking out, then maybe that's a good thing? For Stiles? Maybe. It wouldn't do to be the first Avenger to die of sex.

Not that Stiles cares. He should, but he just… doesn't.

Maybe those asshat psychologists knew what they were saying, after all.

"Don't you ever do that again," he mumbles, into Derek's shoulder, and Derek _freezes_. Whoops. "I mean," Stiles adds, as hurriedly as he can with most of his brain still stubbornly offline, "with the, the not letting me. Touch you back. Why didn't you let me touch you back?"

"It wouldn't have been safe."

Huh. Stiles was right about the Hulking out, then. "Man, you must have the _worst_ blue balls."

Derek chuffs. Which is - which is just odd, because it sounds more like a wolf-laugh than a man-laugh. It's also ridiculously adorable, in a way that nothing to do with the Hulk has any right to be adorable, but it's not like Stiles's sanity has anybody's seal of approval, anyway.

"The others have got a betting pool going. About when we finally - "

"Yeah."

"You _know_?"

"Super-hearing." Derek nuzzles Stiles's ear. "I heard them from across the mansion."

"Whoa. I heard them on the surveillance cameras."

"You spy on your teammates?"

"You eavesdrop on them?"

"Pot."

"Kettle."

This is nice. They're insulting each other playfully. Stiles could get used to this. "You think we could - um, settle their bet? Properly? With mutual orgasms, preferably with penetration? Sooner rather than later?"

Derek does this thing, this strange, canine lick all along Stiles's face, that should feel disturbing or disgusting but instead only makes Stiles laugh breathlessly and flashback to the half-blowjob from last night. "Later."

Oh. "But it _will_ happen."

"Go to sleep."

"Derek - "

"Go. To. _Sleep_."

"You're getting better, though. You're not losing it as much, and you're staying human for longer - "

"Because of you."

"I. Uh?" What?

"Sleep."

"No, seriously, what? I - you're saying _I'm_ the reason you - "

But Derek's palm has just clamped over Stiles's mouth, and his eyebrows have lowered. "Stop. Talking."

"Thotchulykitwenable," Stiles manages to say, which may or may not translate to, _I thought you liked it when I ramble._

But Derek doesn't take his hand off. He just waits, patiently, until Stiles nods.

It occurs to Stiles that this isn't a relationship of mutual respect, or the sort of relationship that Stiles wants to be having -

"If you don't sleep, you won't recover from today's battles. You don't heal as quickly as I do."

…oh.

It _is_ the sort of relationship Stiles wants to be having. The sort that can save a guy's soul and stop him from turning into a ravening werebeast, how cool is that? Stiles had never imagined being someone's Immortal Beloved. It's kind of overwhelming. Brilliant, but overwhelming. Overwhelming, but brilliant.

Jesus.

As Derek slowly relaxes into sleep, muscles unlocking one after another until he isn't lying on Stiles so much as smothering him, Stiles comes to the startling realization that a) he's in a relationship with the Hulk, and that b) he really does need to get that doggy basket.

A very large doggy basket.

With ribbons.

Now that Stiles is relatively certain the Hulk won't kill him, he can take a few liberties. Add a few bells and whistles.

Because, as it turns out, the Hulk does have a handler.

And that handler? Is Stiles.

  


* * *

**fin.**

**Author's Note:**

> Like my writing? Check out [my blog](http://saucefactory.tumblr.com/)!

**Works inspired by this one:**

  * [[podfic] Natural Selection](https://archiveofourown.org/works/609283) by [reena_jenkins](https://archiveofourown.org/users/reena_jenkins/pseuds/reena_jenkins), [Saucery](https://archiveofourown.org/users/Saucery/pseuds/Saucery)




End file.
